Truing apparatus for lapping machines



Jan. 12,1937.

H. S. INDGE TRUING APPARATUS FOR LAPPING MACHINES 2 Sheets-Sheet 1 Filed. April 6, 1936 22 21 20 22 HERBERT 5'. INDG'E Jan. 12, 1937. 5, |NDGE 2,067,531

TRUING APPARATUS FOR LAPPING MACHINES Filed April 6, 1936 2,Sheets-Sheet 2 INVENTOR HERBER T 5'. IND 5-1:

ATT RNEY Patented Jan. 12, 1937 UNITED STATES PATENT OFFICE Herbert S. Indge, Westboro, Mass, assignor to Norton Company, Worcester, Mass, a corporation of Massachusetts 7 Application April 6, 1936, Serial No. 72,869.

Claims.

The invention relates to truing and dressing apparatus for lapping machines.

One object of the invention isto provide a dressing and truing apparatus adapted to dress both the upper andthe lower lapping wheels. Another object of the invention is to. provide a truing or dressing apparatus whereby a lapping wheel may be dressed to. a true conical shape.

Another object of the invention is to provide a dressing or truingapparatus by means of which a lapping wheel may be trued to a flat surface. Another object of the invention is to provide a dressingor truing apparatus for the generation of special shapes. Another object of the invention is to provide a single apparatus achieving many different functions intruing and dressing. Another object. ofthe invention is to provide a dressing or truing apparatus which can be set to dress one wheel to a conical shape and another wheel to a fiat disk shape and to perform one operation after the other without adjustment in between operations.

Another object of the invention is to provide a dressing apparatus using a diamond tool or, interchangeably an abrasive wheel dresser. Another object of the invention is to provide adressing apparatus to shapelapping wheels for the production of conical articles. Other objects of the invention are to provide a truing or dressing apparatus particularly applicable to machines of the type disclosed in Letters Patent Nos. 1,609,269 and 1,831,958. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is shown one of many possible embodiments of the mechanical features of this invention,

Figure 1 is a fragmentary elevation of a lapping machine having truing apparatus embodying the invention;

Figure 2 is a plan view of the truing apparatus detached from the machine;

Figure 3 is a view, partly in side elevation and partly in. section, along the line 33 of Figure 2;

Figure 4 is a plan view of a wheel dressing tool;

Figure 5 is a plan view of the lower part. of a lapping machine, showing the dressing or truing apparatus of the invention and illustrating the dressing or truing of the. lower lap;

Figure 6 is a view similar to Figure 5, showing the dressing or truing of the upper lap.

Referring first to Figures 5 and 6, my invention may be incorporated in or applied to a lapping machine having a machine base l0 and an upstanding column Il. Referring to Figure 1, the machine provides tripod arms I2 supporting a lower drive plate 13 which is rigidly attached to the tripod arms by means of bolts M. A lower lapping wheel chuck l5 rests upon the plate l3 and is constrained to rotate with it, but is preferably given an eccentric motion in accordance with the drive for the lower lap disclosed in patent to Player No. 1,609,269. I preferably provide a lower lapping wheel or disk l6 secured to the chuck 15. In the aforesaid patent to Player, the lap is a metal lap and in the present embodiment of the present invention I substitute a chuck and a lapping wheel, the wheel 16 being formed of bonded abrasive grain. The chuck I5 is preferably operated and driven as shown in the aforesaid patent to Player.

Still referring to Figure 1, I provide an upper lapping wheel 11, preferably also formed of bonded abrasive material. This is held by a suitable chuck i8 which is secured to a holding member l 9 by means of bolts 20'. The holding member 19 may be attached to a conical. driving member 2| by means of bolts 22 or it may be allowed to float upon the central driving spindle, not shown, towhich the conical driving member is attached. The construction of these. parts and the drive for the upper lapping wheel I! may be and preferably are as shown in the prior patent to myself and Sydney Player No. 1,831,958.

Referring now to Figures 1, 5, and 6, I provide a bracket 25 attached in any suitable manner to the column I 1. Referring now to Figure l, I provide a pair of split journal portions 26 and. 21 integral with the bracket 25. A vertical shaft 28 extends through and between the journals 26 and 2'! and lost motion or play is eliminated by means of screws 29 and 30, the screw 29 extending through a pair of bosses 3| and the screw 30 extending through a pair of bosses 32, said bosses projecting from the journals 26 and 21, respectively. Still referring to Figure 1, an arm 33 has a hub portion 34 into which extends the shaft 28. By means of a set screw 35, the hub 34 is firmly attached to the shaft 28. This arm 3.3 transmits the oscillatory movement to the shaft 28 for dressing or truing the lower lapping wheel [6, as will be described. The journal 26 is of less diameter than the journal 21 and there is a shoulder upon the shaft 28 under which is located a washer 36 locking screws 92 having operating arms 43, the I screws 42 passing through bosses 94 extending from the collar 88. As shown in" Figure l, I may further provide a split supporting collar 55 to support the collar 88 while angular adjustmentsare being made thereof on-Ithe shaft 28.

Referring now particularly to Figures 1, 2, and

3, I provide a vertically movableslide 58 having ways 5I fitting upon the ways 4|. The slide 58 is hollow and has two vertical sides and'a top; in"

the top is a saw ,cut 52 and by means of bolts 53 operated by arms 59,, the ways 5i ,may be clamped upon the ways 4| to hold theslide 59'rigid1yu'pon the collar 48, the bolts '53 .passing through the opposite vertical sides of the slide 58. However, when the bolts53 are loosened, the slide 58 may be moved vertically by turning a knurled head 55. The knurled head 55 is pinned toa vertical screw shaft 56 which passes through a journal portion 51 of the slide 58. By means of this head 55 and an enlarged diameter portion 58 onthe screw 56, the shaft 56,, is thrust journaled in both directions. The screw 56 passes into a nut 59 which has a projecting stud-portion 68 extending into the collar 48.

Referring now to Figures 2 and 3, the slide 58' has .anannular portion 6I into whichextends a cylindrical pilot portion 62 of a swivel head 63. I provide a bolt 64 and a pair of bolts 65, the heads of the latter being located in cut-outs 66 of the swivel head 63. These three bolts 64 and 65 secure the swivel head 63 to the slide 58, and insomuch as bolts 64 and 65 pass through arcuate slots in the swivel head 63 angular adjustment of the swivel head 69 upon the slide 58 may be made between limits.

Still referring to Figures 2 andS, the swivel .head 63 has dovetailed ways supporting a slide 61 with corresponding slideways' 68. A screw shaft 69 extends into a threaded portion I8 of the swivel head 63 which constitutes in effect a nut; the

.screw shaft 69 has an enlarged portion II which abuts the end of the slide 6! and is also held by a plate 12, thus to prevent longitudinal movement of the screw shaft 69 relative to the slide 6?.

Screw shaft 69 is journaled in a journal portion I8 formed on the plate I2 and the screw shaft 69 has a hand wheel I4 keyed to it. The hand wheel I4 is retained in position by. means of a nut I5. By rotating the hand wheel I8, the slide 61 can be moved rectilinearly along the ways 66, which extend perpendicular to the axis of angular adjust- .ment of the swivel head 63.

are tightened, the front portion of the clamp I9 engages the upperpart of a dovetailed slide 8|. This dovetailed slide 8| is arcuate in plan view and its opposing edges fit between the slide portion I6 and the overhanging portion of the clamping slide member I9. The dovetailed slide BI is integral with a cylindrical dresser holder 82 in which is mounted cylindrical dresser holders 83 I having plugs 84 and 85 in which are embedded diamonds 86 and 81.

Referring now to Figure 4, for the dressing tool just described can be substituted a dressing tool comprising a dovetailed arcuate slide 88 having a pair of arms 89 forming a fork, which fork has journal portions 98 receiving a trunnion 9| of an abrading wheel 92. The abrading wheel 92 may be of bonded abrasive material. For example, if the lapping wheels I6 and I I are of silicon carbide bonded with fired ceramic bond, the dressing wheel 92 may be of silicon carbide abrasive grain bonded with fired ceramic bond and of coarser grain'size and wheel 92 will dress the lapping Wheels.

In order to swing the collar 48 and all parts secured thereto including the dressing tool including either the diamonds 86, 81 or the dressing wheel 92, I provide, as is better shown in Figure l, a swivel journal member 95 through the lower part of which extends a screw shaft 96, the journal 95 providing a thrust bearing for the shaft 96. To the outer end of thescrew shaft 96 is fixed a hand wheel 91. The swivel journal member 95 includes an upstanding stud portion 98 which extends through a journal portion 99 on the end of y the arm 33.

Referring now to Figures 5 and 6, thescrew shaft 96 extends through a swivel nut I88 which is free to oscillate on a vertical axis, being mounted in a swivel nut holder I III which in turn Referring now to Figure 1, the swivel head 63 is adjusted upon the slide 58 so that the slide 61 will move at an angle to the axis of the shaft 28 which is the same as the angle between an element of the conical surface I85'to be formed on the upper lapping wheel I1 and an element of the cylindrical surface of the lapping wheel I6. Insomuch as the shaft 28 is preferably vertical, when the swivel head 63 is adjusted so that the slide 6! Imoves horizontally, the dressing tools .will form a cone I85 whose apex angle'is that is to say f. it will be a fiat plane surface. From that condition any angular adjustment of the swivel head 63 produces a conical surface on the lower side of the upper lapping wheel I-I, either a concave or a convex cone, as is desired. Preferably I provide a scale I86 on the swivel head 63 and a marking I 8'! on the slide 58 in order to facilitate setting of the swivel head. 7

Referring now to Figure 6, with the parts so set I adjust the collar 48 angularly by turning the 1.

stop plate II8 secured to the column II in order securely to hold the partsin this position of angular adjustment. I may. now dress the upper wheel I! simply by rotating the hand wheel I4, it

being understood that the upper spindle is rotating. If, however, I am lapping conical rollers with p the use of a cage such as shown in Patent No.

1,689,269 already referred to, the dressing tool should be caused to advance onan angle to the tangent which is-the same as that of the slots of the cage, as shown in said patent, in order to gen- ;.75

erate special surfaces upon the work pieces. In such event, a different adjustment will be made and the cage can be used as a template to set the angle of the advance of the dressing diamond 86 in a horizontal plane.

After the upper lap !l is dressed or trued in accordance with the foregoing, the lower lap may be dressed or trued without disturbing the adjustment of the swivel head 63 simply by lowering the slide 56 by turning the knurled head 55 after loosening the bolts 53, until the diamond 81 contacts with the lower lapping wheel Hi. The hand wheel 14 should not be touched during this operation and, referring to Figure 5, traverse of the dressing diamond is effected by rotating the hand Wheel 91. The lower lapping wheel l6 has a compound movement but if the diamond is moved slowly over its surface, every part thereof will be trued to a plane.

Thus without disturbing the adjustment of the apparatus for dressing the upper wheel, the lower wheel can be trued and vice versa. Instead of dressing the wheel ll first, the wheel l6 may be dressed first. Furthermore, instead of moving the diamond 81 down to the wheel IE, it may be initially placed in such position and the upper wheel Il may be moved down to the upper diamond 86.

The dressing device shown in Figure 4 may be substituted for the diamonds and holder and in such event the wheel 92 is skewed with respect to the movement of the other wheels. The arcuate dovetailed slide 88 has a wide arc, for example 90, and wide adjustments are thereby permitted. The axis of the wheel 92 can advantageously be placed at an angle of about 45 to a radial line of the wheel being dressed at the median point of contact.

From the foregoing description, it will be seen that the dressing tool may be moved by the hand wheel M for one operation and by the hand wheel 91 for another operation. The dressing tool is universally adjustable by the various slides, journals, stops and screws described; nevertheless I have provided rigid locking devices to remove all play in the parts once the adjustment is made. This is an important feature in a dressing apparatus for lapping machines where tolerances on the work piece must be maintained within limits of one-tenth of a thousandth of an inch or finer.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:-

1. In apparatus of the class described, a first slide, a slideway for said first slide, trunnioning means carried by said first slide the axis whereof is perpendicular to elements of the slide-way for the first slide, a second slideway mounted on said trunnioning means with elements of said second slideway perpendicular to the axis of said trunnioning means, a swivel mounting for said slideway for said first slide, a second slide mounted on said second slideway, and a dressing tool mounted on said second slideway.

2. In apparatus as claimed in claim 1, the combination with the parts and features therein specified of a hand wheel to control the swivel mounting for the slideway for the first slide.

3. In apparatus of the class described, a mounting for a dressing tool permitting it as a unit to be oscillated in a horizontal plane, a further mounting for said tool permitting it to be rectilinearly moved at an angle to the horizontal plane, and separate means respectively to control the dressing tool on said mountings.

4. In apparatus of the class described, a dressing tool, a mounting for said dressing tool permitting oscillation thereof in a plane, a further mounting for said tool permitting rectilinear movement, a still further mounting for the tool to set the line of rectilinear movement at a desired angle to the said plane from parallelism to an appreciable angle, and screw feeding means for effecting the oscillation.

5. In apparatus of the class described, a dressing tool, a mounting permitting oscillation thereof in a plane, a further mounting for said tool permitting rectilinear movement, a still further mounting for the tool to set the line of rectilinear move-ment at a desired angle to the said plane from parallelism to an appreciable angle, and feeding means for effecting the rectilinear movement.

6. In apparatus as claimed in claim 4, the combination with the parts and features therein specified of a still further mounting for moving the tool substantially perpendicularly to the plane of oscillation.

7. In apparatus as claimed in claim 5, the combination with the parts and features therein specified of a still further mounting for moving the tool substantially perpendicularly to the plane of oscillation.

8. In apparatus of the class described, a vertical shaft, a collar on said vertical shaft, a hand wheel and mechanism to swing the collar on said shaft, a vertical slideway on said collar, a vertically movable slide carried by said slideway, a trunnion carried by said slide, a swivel head car ried by said trunnion, a slideway on said swivel head, a slide mounted on said last named slideway, hand wheel and mechanism to move said last named slide on said slideway, and a dressing tool carried by said last named slide.

9. In apparatus of the class described, a lower lapping wheel, an upper lapping wheel, a holder for a pair of dressing diamonds one above and one below the holder, means to move the holder slowly in an arcuate path the plane of which is parallel to the lapping plane of the lower lapping wheel, means to move the holder rectilinearly, and means to adjust the path of rectilinear travel of the holder to cause said path to assume various angles to the plane of the lower lapping wheel whereby to dress the upper lapping wheel to a given conical surface.

10. In apparatus as claimed in claim 9, the combination with the parts and features therein specified of means for moving the holder parallel to the axis of one of the lapping wheels.

HERBERT S. INDGE. 

